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<head lang="en">
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    <title></title>
    <style>
        *{margin:0;padding:0}
        .row:before{
            display: table;
            content:''
        }
        .row:after{
            display: table;
            content:'';
            clear:both;
        }
        .header{width:1000px;height:40px;background:pink;line-height: 40px;margin-left:auto;margin-right:auto}
        ul{list-style: none;}
        a{text-decoration: none}
        li{float:left;width:100px;}
        li.dropdown{position:relative}
        .dropContent{position:absolute;width:100px;background-color: deeppink;display:none;box-shadow: 0 1px 2px 0px gainsboro}
        .row a{display:block;text-align: center;color:white}
        a:hover{color:gainsboro;background:palevioletred}
        .dropdown:hover .dropContent{
            display: block;
        }
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